Bed-motion for printing-machines.



D. J. SCOTT & C. E. DRANGE.

BED MOTION FOR PRINTING MACHINES.

APPLICATION FILED JULY [0. 1914.

Patented June 18, 1918.

5 SHEETSSHEET l.

D. J. SCOTT & C. E. ORANGE.

' BED MOTION FOR PRINTING MACHINES,

APPLICATION FILED JULY 10, 1914- Patented June '18, 1918..

5 SHEETSSHEET 2.

51 WWW/$0M Dal/m J. 500% v Cami Eflrawe D. J. SCOTT & C. E. ORANGE.

- BED MOTION FOR PRINTING MACHINES.

APPLICATION FILED JULY 10. 1914.

5 SHEETS-SHEET 3.

Patented June 18, 1918.

D. I. SCOTT (I; C. E. ORANGE. BED MOTION FOR PRINTING MACHINES.

APPLICATION FILED JULY I0. I914- Patented June 18, I918.

' 5 SHEETS-SHEET 4.

n. .1. soon & c. E. ORANGE.

BED MOTION FOR PRINTING MACHINESx APPLICATION FILED JULY 10. 1914.

MKIZM ioivirnn erase rarnnr DAVID JOHN SCOTT AND CARL EBEBHARD DRANGE, OF PLAINJFIELD, NEW JERSEY, ASSIGNORS 'IO ISABELLA SCOTT AND DAVID J. SCOTT, EXECUTORS 0F WALTER "scorer, DECEASED,

LATE OF PLAINFIELD, NEW JERSEY.

BED-MOTION FOR PRINTING-MACHINES.

Specification of Letters Patent.

Patented June 1%, llfild.

Application filed July 10, 1914. Serial No. 850,101.

To all whom it may concern:

Be it known that we, DAVID J. SCOTT and CARL E. DRANGE, both citizens of the United States, and residents of Plainfield, in the county of Union and State of New Jersey, have invented certain new and useful Improvements in Bed-Motions for Printing- Machines, of'which the following is a specification.

The present invention relates to printing machines in which at least one of the printing members partakes of a reciprocating movement, either in a rectilinear path or in a curvilinear path, this type being well exemplified by the ordinary two revolution flat bed machine now so commonly used.

It is a well known fact that the speed of presses of this character is limited, and that the chief factor of limitation of speed resides in. the heavy reciprocating bed, in some instances weighing several tons, which has to be reversed at the end of each stroke.

Among the numerous constructions that have been heretofore devised to eifectreversal of the bed, the so-called harmonic crank motion is the one most generally utilized. This construction usually consists of a roller mounted on the bed driving gear, which roller engages between shoes or members forming a straight slot at each end of the bed. The bed driving gear usually makes three revolutions to each cycle of the machine, two revolutions being utilized to impart the main reciprocating movements to the bed, and one-half of a revolution being used at each end to decelerate, stop and accelerate the bed up to speed. In other words one-half of a revolution of the crank roller is utilized to reverse the bed at each end, of which one-quarter is used to stop the bed and the other quarter of a revolution is utilized to bring the bed up to speed. 'Since the crank roller moves at a uniform angular speed, its eifective speed, '2'. 6., the amount of movement imparted by it through the straight slots to the bed, will vary directly as the natural cosines of the crank. It follows therefore that during the greater part of the quarter revolution allowed to bring the bed to a standstill, the bed is slowed down comparatively little, so that by far, the greater portion of the work of the crank in stopping the bed must be accomplished during less than half of a. quarter of a revolution of the crank.

As a result there is considerable strain and jar on the press at each end of the stroke of the bed, and, while air cushions are usually employed to minimize this effect, the practical speed at which large presses of this kind can be operated satisfactorily is naturally more limited than it would be if the reversing action were better equalized.

The chief object of the present invention is to distribute the reversing action more evenly throughout the half revolution of the crank during which the bed is reversed so as to reduce the amount. of strain and jar to which the machine is subjected, thereby making it possible to largely increase the speed at which the press can be operated.

In carrying out the foregoing and other objects of the invention, we employ a crank means for reversing; the bed at a lagging crank ratio. Such a crank means is most easily understood when explained in connection with a construction employing a connecting rod and a sliding cross head; In such a construction the cross-headmo'ves a distance equal to twice the radius of the crank while the crank is moving through an arc of 180, that is from one point in line with the radially moving cross-head on' one side of the center of rotation of the crank to the opposite point on the other side of the center of rotation. During the first 90, however, the cross-head moves a greater distance than the radius of the crank, While during the latter 90 the cross-head moves a lesser distance than the radius of the crank. We have found that the movement of the cross-head during the latter or lagging portion of the revolution of the crank departs but little from a uniform decelerating motion and that therefore the reversal of the bed can be accomplished during this period without subjecting the machine to any undue strain or jar.

Other features of construction, combination of parts and arrangement of elements will appear as the specification proceeds.

In the accompanying drawings the invention is disclosed in several concrete'and-preferred forms, but changes of construction may be made without departing from the legitimate and intended scope of the invention as expressed in the appended claims.

In the said drawings:

Figure 1 is a side elevation of a machine embodying the invention.

Fig. 2 is a plan view of the driving elements of the bed.

Fig. 2* is a detailed view of the bed driving means and associated elements.

Figs. 3 to 8 inclusive are diagrammatic views showing the various positions assumed by the reverslng elements during one complete reciprocation of the bed.

Figs. 9, 10, 11 and 12 are diagrammatic views of modifications of the invention.

Fig. 13 is a diagrammatic view of the action of a harmonic crank.

Fig. l-it is a diagrammatic view of the action of a lagging crank.

Similar characters of reference indicate corresponding parts in the several views.

Referring to the diagram Fig. 13 the effect of the harmoniccrank upon the movement of the bed during the deceleration of the bed is shown. The distances given are figured on the basis of a crank having a radius of 10 inches and are taken from a standard table of natural sines and cosines. For convenience, the 90 degrees from full speed to standstill of the bed have been divided into 10 equal parts, each representing 9 degrees,

and the cosines of the different degrees are shown, as well as the difference in length of the cosines, thereby indicating the actual travel between degrees. The uniform speed of the crank during each ninedegrees is here given at 1.5708.

In comparing this diagram with the full surface'speed of the crank pin during each 9 degrees of rotation it will be seen that when the crank pin has moved about 45 degrees the speed of the bed is practically threefourths of the full speed. In other words, it has been slowed down less than 30 per cent. It will further be seen that thereafter the rate of slowing down the'bed increases at a very great ratio, particularly during the last three-tenths of the quarter revolution when the speed of the bed is brought from about one-half of its uniform travel to a complete standstill.

For the purpose of comparison and with the object of more clearly revealing the nature of the present invention there is shown in Fig. 14 a diagram of the lagging crank effect. The quarter revolution. of the crank during which deceleration takes place has been chosen for illustration and the length of the crank pin is here given as 10 inches and the connecting red as 25 inches, that is to say, the connecting rod is two and one-half times the length or throw of the crank. The movement of the cross-head at the other end of the connecting rod has been plotted and the actual distance that the bed travels during each nine degrees of travel of the crank is given. The uniform speed is the same as before, namely, 1.5708.

The formula which has been used to. calculate the travel of the cross-head and which is applicable to any motion of this kind rcgardless of the radius of the crank or length of the connecting rod is:

Let

D distance of travel of cross-head rad-:radins of crank Lzlength of connecting rod sin sine of angle cos cosine of angle D /L sin +rad. cos L.

From this formula and Fig. 14:, which illustrates the lagging effect of a crank and connecting rod in proportion to give the best reversal effect on a standard single color two revolution press, it will be seen that after one-quarter of the movement of the crank pin that is required to bring the bed from full speed to a standstill has been made, the bed travels at nearly three-quarters of its full speed. When one-half of the motion has been made, the bed travels at nearly half speed. After three-quarters of the stroke, it travels nearly at one-quarter speed, etc., and the result obtained from this lagging crank reverse is that the bed can be reversed more efficiently and with less shock since, during the beginning of the reverse, the bed is decelerated more rapidly, leaving less work for the remaining portion of the reverse.

During the next quarter revolution of the crank the bed will be accelerated in the opposite direction in the same ratio that it was decelerated, the lagging crank effect obtaining during one-half of the revolution of the crank. When the crank passes the vertical plane it will enter the gaining portion of its cycle and will during the next quarter revolution move the cross-head a distance greater than its radius. The same effect of course occurs during the fourth quarter of the revolution while the crank is moving from the horizontal to the vertical. It will be noted that at the moment of reverse. the cross-head is nearest the center of rotation of the crank and that during reversal of the bed, that is from the moment the crank pin assumes control of the bed until it rellnquishes control, said crank is traveling through that are of its movement which is on the side of the center of its rota.- tion opposite to the one on which the crosshead is located.

The amount of lag of the cross-head is here controlled by the length of the connecting rod in relation to the length of the crank and therefore by varying these dimensions in different presses the best reversing conditions applicable to each size and type of machine may readily be determined, the formula given being-applicable to all forms. It will therefore be understood thatjit "is not intended that this invention shall be limited to the use of a connecting rod exactly two and one-half times the length of the reversing crank, nor indeed to a construction in which a connecting rod is used. In high speed machines the proportions would naturally be different from the re verse used on slower machines, such as two color printing machines Where the weight of the type bed is nearly double that of ordinary single color machines and where the angularity of the connecting rod is a factor that must be taken into consideration in its relation to the side thrust on the cross-head.

One of the fundamental difierences between the lagging crank reverse above described and the standard harmonic reverse is that in the lagging crank reverse the distance traveled by the bed from the moment the reverse motion assumes control until'it is brought to a standstill is less than the radius of the reversing crank, while in the.

harmonic reverse the movementof the bed is equal to the radius of the crank.

Referring now to the construction shown in 'Figs. 1 and 2, 1 is the impression cylinder which may be mounted to rise and fall in any well-known manner, it being in its lower position during the uniform printing stroke and in its upper position during the return stroke. 2 is the type bed of the press carrying the form and is reciprocated back and forth once during each cycle of the ma chine. (Jarried by this bed are the printing stroke driving rack 3,.tl1e return strokedniv ing rack l, which are of equal length, and the short reversingracks and 6 also of equal length but of lesser length than the main racks, one of said reversing racks being used for reversing the bed at each end of the main stroke.

Suitably mounted in the frame 7 is the driving shaft 8 carrying on its inner end the printing stroke driving gear 9 and this geai 9 always meshes with the return stroke driving gear 10 which is mounted ona suitable stud. This return stroke driving gear 10 is double faced. or double width, one face or width meshing continually with the printing stroke driving gear 9 and theother face engaging at intervals with the return stroke driving rack 41;. 11 indicates the re versing crank shaft mounted in the frame and carrying the reversing crank 12 with a crank pin 13. On this crank pin 13 are mounted side by side the connecting rods 14- and 15. the reversing members here taking the form of sliding racks 16 and 17 suitably connected to the connecting rods.

Thesereversing crank racks 16 and 1711119511 respectively with the reversing pinions 14.8

stroke driving ,gear 10.

and

19 mounted on studs having fixed centers of rotation. The different members are ingcrank driving gear 22. Also the small driving pinion 23 at the end of the main driving shaft 8 engages with the gear 24 mounted on the cam shaft 25 and on this cam shaft is carried the cam 26 that serves to shift printing stroke drivinggear 9 and return stroke driving gear 10 sidewise on their respective shaft and stud during each reverse so as to engage them in the proper manner either with the printing stroke driving rack 3 or with the return stroke driving rack 45 in a manner that is well understood in the art. In the present instance this periodic shifting of the gears 9 and 10 is accomplished from the cam 26 by means of the shifting fork 27.

' In the practical construction of the two revolution press the cylinder 1 makes two revolutions during each cycle of the machine and the main driving shaft 8 is .geared to make six revolutions during each cycle of the machine while the reversing crank shaft 11 makes three revolutions and the cam shaft 2'5 makes one revolution.

This is necessary in order to time the parts properly.

The operation of the machine is as follows;

The bed is driven on its uniform printing stroke by the gear 9 (the face of the gear 10 which meshes continually with gear 9 clears the bed printing rack 3 because in the .present embodiment the gear 10 is of smaller diameter). At the end of the uniform printing stroke the printing stroke driving gear 9 runs out of the right-hand rend. of the printing stroke driving rack 3 at the moment that the reversing rack 5 meshes with the reversing pinion 18 (see Fig. 3), at which time the reversing crank 12 stands in a vertical position directly above the reversing crank shaft 11. During the continued rotation of the reversing crank shaft 11, in the direction indicated, the bed 2, by means of connecting rod 14:. reversing crank rack 16 and reversing pinion 18 is gradually reduced in speed in the manner and ratio described until the re .versing crank 12 stands at the right-hand dead center. at whichtime the bed is at a standstill. (See Fig. 1-.) Continued rotation of the c ank shaft 11 reverses the direction of travel of the bed and accelerates it gradually until the moment when the crank 12 is standing vertically directly below crankshaft- 11 when. the bed 2 is traveling at the full surface speed of the return See Fig. 5.) At this' moment the reversing rack 5 runs out .of .r-nesh with thereversing pinion l8 and at the same time the return stroke driving gear meshes with the return stroke driving rack 4 after which the bed travels at a uniform speed on its return stroke until the return stroke driving gear 10 has reached I the left-hand end of the return stroke driving rack 4. At this moment the reversing rack 6 is just starting into mesh with the reversing pinion 19 and the reversing'crank 12 is standing vertically with the crank pin directly below the crank shaft 11. (See Fig. 6.) When in this position continued rotation of the crank shaft 11 through the connecting rod 15, reversing crank rack 17 and reversing pinion 19 gradually reduces the speed of the bed 2 in the manner and ratio described until the crank pin 18 is at the left-hand dead center, (see Fig. 7), at which time the bed 2 has come to a standstill at the extreme right-hand end of the machine. Continued rotation of the crank reverses the direction of movement of the bed and gradually accelerates it until full printing speed is reached at which time the crank pin 13 stands vertically above the reversing crank shaft 11 and the reversing pinion 19 is running out of mesh with the reversing rack 6 while at the same time the printing stroke drivinggear 9 is starting into mesh with the printing stroke driving rack 3. (See, Fig. 8.) When not engaged in reversing the bed, the rotation of the crank shaft 11 by means of the connecting rods 14 and 15 and reversing crank racks 16 and 17, idly oscillates the reversing pinions 18 and 19.

It will be noted here that the gaining and lagging effective movement of the crank is both with respect to its own uniform surface speed and with respect to the uniform surface speed of the bed.

It will further be seen that the reversing members here take the form of racks 16 and 17 which reciprocate in a rectilinear direction.

In Fig. 9 is shown a similar arrangement except that the crank has less throw and.

that its surface speed is not equal to the uniform printing speed of the bed. In order to compensate for this diiference'the racks 16 and 17 here engage with the pinions 18 and 19 and mounted on the studs of these pinions are larger pinions 28 and 29 which engage directly with the reversing racks 5 and 6 on the bed, thereby giving.

the small crank the same effect as a crank whose surface speed is equal to the speed of the bed. I

In Fig. 10 there is shown a construction in which only one connecting rod is employed. It is of course not possible to use the same half revolution of the crank for reversing the bed at both ends. quently the crank shaft in this instance makes four revolutions to each cycle of the I present application.

(louse-- 'to obtain the lagging effect on the reverse.

As here shown the crank 12 is connected by means of the connecting rod 30 to a reciprocating member 31, which is provided with oppositely facing racks 82 and 33 engaging with corresponding reversing pinions 18 and 19 which in turn mesh with racks 5 and 6.

In Fig. 11 two crank shafts 34 and 35 are utilized each having a crank 36 and 37 and connected by means of connecting rods 38 and 39 to the reversing members 40 and 41 which here take the form of reciprocating members moving in a curvilinear path or, in other words, oscillating levers which engage with hooks 42 and 43 on the bed, said hooks being mounted to oscillate on a pivotal support, as shown, and having cam rolls 44 and 45 engaging with cams 46 and 47 stationary on the framework and adapted to move the said hooks into and out of engagement with the members 40 and 41.

In Fig. 12 the invention is shown applied to an ordinary slot construction. In this instance the bed is provided with upper and lower racks 48 and 49 and at each end with a concave slot 50 formed between the shoes 51. One of these shoes is movable in and out in a Well-known manner. 52 is the main bed driving gear which alternately engages the opposite racks 48 and 49, said racks being in different vertical planes and said gear 52 being shifted sidewise in a well-- known manner. 53 is a crank carried by said bed driving gear 52 and engaging in the slots 50 during the reversal of the bed. It will be noted that the shape of the slots 50 is concave and differs from the ordinary construction which is either straight or convex and by this means the bed is reversed at a lagging crank ratio in the same 1uanner as previously described, the amount of lag being determined by the curvature of the reversing slot.

While the form of the invention shown in Figs. 1 to 8 inclusive has been described in detail, it is not intended to specifically claim the details of this construction in the specifically claim in this application the form of the invention in which the means that impart the main reciprocating movements to the bed are separate from the reversing means.

It will also be noted that in the form of the invention shown in Figs. 1 to 8 inclusive the thrust exerted upon the crank shaft during the period of reversal is in a direction opposite to the direction of the thrust of the bed, the two thrusts thereby tending to equalize each other. This is brought about by the interposition of the reversing pinions 18 and 19. This feature of the invention is the subjectmatter of anoth r application,

incense Serial No. 850,102, filed July 10, 1914:. These features are both claimed in one application, Ser. No. 864,119 filed September 29, 1914.

What is claimed, is: 1. A printing machine comprising cooperating printing members, one of whlch has a reciprocating movement, crank means operatively included in the machine, and connecting means between the crank means and the reciprocating member for effecting the reversal of the movement of the latter at each end of its stroke at a lagging crank ratio occupying one-half of the revolution of the crank means, whereby there is effected a minimum length of travel of the reciprocating means coupled with a maximum degree of uniformity of deceleration and acceleration of the bed during such reversals.

2. A printing machine comprisingcoopcrating printing members, one of which has a reciprocating movement, crank means, means for rotating the crank at a uniform speed, and connecting means between the crank means and the reciprocating member for effecting the reversal of the movement of the latter at each end of its stroke at a lagging crank ratio occupying one-half the revolution of the crank means, whereby the rates of deceleration and acceleration of the reciprocating member during the reversals 'of movement are uniform and equal.

3. A printing machine comprising cooperating printing members, one of which has a reciprocating movement, crank means having a fixed throw operatively included in the machine, and connecting means between the crank means and the reciprocating member for effecting the reversal of the movement of the latter at each end of its stroke at a lagging crank ratio occupying one-half the evolution of the crank means, whereby ihere is effected a minimum length of travel of the reciprocating member coupled with a maximum degree of uniformity of deceleration and acceleration during such reversals.

4. A printing machine comprising coopcrating printing members, one of which has.

a reciprocating movement, crank means having a fixed throw, means for rotating the crank at a uniform speed, and connecting means between the crank means and the reciprocating member forefiecting the reversal of the movement of the latter at each end of its stroke at a lagging crank ratio occupying one-half the revolution of the crank means, whereby there is effected a minimum length of travel of the reciprocating member coupled with a maximum degree of uniformity of deceleration and acceleration during such reversals.

5. A printing machine comprising cooperating printing members, one of which has a reciprocating movement, crankmeans operatively included in the machine having a gaining and a lagging effective movement with respect to its surface speed, and connecting means between the crank means and the reciprocating member for reflecting the reversal of the movement of the latter at each end of its stroke, the reversing operation being coextensive with the lagglng portion of the movement of the crank means, whereby there is effected a minimum length of travel of the reciprocating member coupled with a maximum degree of uniformity of deceleration and acceleration of the reciprocating member during such reversals.

6. A printing machine comprising cooperating printing members, one of which has reciprocating movement, crankmeans having a gaining and a laggin efiective move ment with respect to its sur ace speed, means for rotating the crank means at a uniform speed, and connecting means between the crank means and the reciprocating member for eflecting the reversal of the movement of the latter at each end of its stroke, the reversing operation being coextensive with the lagging portion of the movement of the crank means, whereby there is effected a minimum length of travel of the reciprocating member coupled with a maximum degree of uniformity of deceleration and acceleration of the reciprocating member during such reversals.

7. A printing machine comprising cooperating printing members, one of which has a reciprocating movement, crank means op eratively included in the machine having a gaining and a lagging movement with respect to the surface speed of the reciprocating printing member, and connecting means between the crank means and the reciprocating member for effecting the reversal of the movement of the latter at each end of' its stroke, the reversing operation being coextensive with the lagging portion of the movement of the crank means, whereby there is effected a minimum. length of travel of the reciprocating member coupled with a maximum degree of uniformity of deceleration and acceleration of the reciprocating member during such reversals.

8. A printing machine comprising 00-;

ingmember coupled with a maximum degree of uniformity of deceleration and acceleration of the reciprocating member during such reversals.

9. A printing machine comprising cooperating printing members, one of which has a reciprocating movement, crank means havinga fixed throw operatively included in the machine, and connecting means between the crank means and the reciprocating member for efiecting the reversal of the movement of the latter at each end of its stroke by causing a movement of said reciprocating member during its reversal less than twice the radius of the throw of the crank means, said reversal operation being coextensive with one-half of the revolution of the crank means.

10.21 printing machine comprising cooperating printing members, one of which has a reciprocating movement, crank means having a fixed throw, means for rotating the crank means at a uniform speed, and connecting means between the crank means and the reciprocating means for effecting the reversal of the movement of the latter at each end of its stroke by causing a movement of said reciprocating member during its reversal less than twice the radius of the throw of the crank means, said reversal operation being coextensive with one-half of the revolution of the crank means, whereby there is effected a minimum length of travel of the reciprocating member coupled with a maximum degree of uniformity of deceleration and acceleration of the reciprocating member during such reversals.

11. A. printing machine comprising cooperating printing members, one of which has a reciprocating movement, crank'means operatively included in the machine havin a fixed throw but a gaining and a lagging e fective movement with respect to its surface speed, andconnecting means between the crank'means and the reciprocating member for effecting the reversal of the movement of the latter at each end of its stroke during the lagging portion of the movement of the crank means, said reversal operation being coextensive with the lagging portion of the movement of the crank means, wherebythe reciprocating member during its reversal moves less than twice the radius of the throw of the crank means.

.12. A. printing machine comprising cooperating printing members, one of which has a reciprocating movement, crank means having a fixed throw. but a gaining and a lagging efiective movement with respect to its. surface speed, means for rotating the crank means at a uniform speed, and connecting means between the crank means and the reciprocating member for effecting the reversal of the movement of the latter at each end of its stroke during the lagging portion of the movement of the crank means, said reversal operation being coextensive with the lagging portion of the movement of the crank means, whereby the reciprocating member during its reversal moves less than, twice the radius of the throw of the crank means.

13. A printing machine comprising cooperating printing members, one of which has a reciprocating movement, crank means operatively included in the machine having a fixed throw but a gaining and a lagging efi'ective movement with respect to the surface speed of the reciprocating printing member, and connecting means between the crank means and the reciprocating member for effecting the reversal of the movement of the latter at each end of its stroke during the lagging portion of the movement of the crank means, said reversal operation being coextensive with the lagging portion of the crank means, whereby said reciprocating member during its reversal moves less than twice the radius of the throw of the crank means, and whereby the rate of deceleration and acceleration of the reciprocating member during the reversals of movement is uniform.

1 1. A printing machine comprisingcooperating printing members, one of which has a reciprocating movement, crank means having a fixed throw but a gaining and a lagging effective movement with respect to the surface speed of the reciprocating printing member, means for rotating the crank means at a uniform speed, and connecting means between the crank means and the reciprocating member for effecting the reversal of the movement of the latter at each end of its stroke during the lagging portion of the movement of the crank means, said reversal operation being coextensive with the lagging portion of the crank means, whereby said reciprocating member during its reversal" moves less than twice the radius of the throw of the crank means and whereby the rate of deceleration and acceleration of the reciprocating member during the reversals of movement is uniform.

15. A printing machine comprising cooperating printing members, one of which has a reciprocating movement, crank means operatively included in the machine, and connecting means between the crank means and the reciprocating member for effecting the reversal of the movement of the latter at each end of its stroke at a lagging crank ratio and during substantially one half revolution of the crank means.

16. A printing machine comprising cooperating printing members, one of which has a reciprocating movement, crank means, means for rotating the crank at a uniform speed, and connecting means between the crank means and the reciprocating member 1,2ee,eea

for effecting the reversal of the latter at'each end of its stroke at a lagging crank ratio and during substantially one half revolution of the crank means, whereby there is effected a minimum length of travel of the reciproeating member coupled with a maximum degree of uniformity of deceleration and ac celeration of the reciprocating member during such reversals.

17. A printing machine comprising cooperating printing members, one of which has a reciprocating movement, crank means having a fixed throw operatively included in the machine, and connecting means between the crank means and the reciprocating member for effecting the reversal of the movement of the latter at each end of its stroke at a lagging crank ratio and during substantially one half revolution of the crank means, whereby there is effected a minimum length of travel of the reciprocating member coupled with a maximum degree of uniformity of deceleration and acceleration of the reciprocating member during such reversals.

18. A printing machine comprising cooperating printing members, one of Which has a reciprocating movement, crank means having a fixed throw, means for rotating the crank at a uniform speed, and connecting means between the crank means and the reciprocating member for effecting the reversal of the movement of the latter at the end of its stroke at a lagging crank ratio and during substantially one half revolution of the crank means, whereby there is effected a minimum length of travel of the reciprocating member coupled with a maximum degree of uniformity of deceleration and acceleration of the reciprocating member during such reversals.

Signed at Plainfield, in the county of Union and State of New Jersey, this 8th day of July, A. D. 1914.

DAVID JOHN SCUTT. CARL EBERHABD; DRANGE.

Witnesses:

JACOB V. Conn, J. W. DICKINSON.

toplet of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington. D. G.

It is hereby certified that in Letters Patent No. 1,269,865, granted June 18, 1918, upon the application of David John Scott and Carl Eberhard Drange, of Plainfield, New Jersey, for an improvement in Bed-Motions for Printing-Machines, errors appear in the printed specification requiring correction as follows: Page 4, line 120, after the period, insert the sentence Ilhesefeatares are both claimed in one application, Serial No. 864,119, filed September 29, 1914;; page 5, strike out lines 2-4 and that the said Letters Patent should be read With these corrections therein that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 13th dayof August, A. 1)., 1918.

[SEAL] F. W. H. CLAY,

Acting Commissioner of Patents. C1. 74-98. 

